VMware Workstation 4.5

Installing an Operating
System onto a
Raw Partition from a Virtual Machine

Installing an Operating
System onto a
Raw Partition from a Virtual Machine

In some situations, you may want to install a guest operating system directly on a physical disk or partition  known as a raw disk  even if you do not need to boot that disk on the host, outside of the virtual machine.

It is possible to use either an unused partition or a completely unused disk on the host as a disk in the virtual machine. However, it is important to be aware that an operating system installed in this setting probably cannot boot outside of the virtual machine, even though the data is available to the host.

Caution: Raw disks are an advanced feature and should be configured only by expert
users.

VMware Workstation uses description files to control access to each raw disk on the system. These description files contain access privilege information that controls a virtual machine's access to certain partitions on the disks. This mechanism prevents users from accidentally running the host operating system again as a guest or running a guest operating system that the virtual machine is not configured to use. The description file also prevents accidental writes to raw disk partitions from badly behaved operating systems or applications.

Use the New Virtual Machine Wizard to configure VMware Workstation to use existing raw disk partitions. The wizard guides you though creating a new virtual machine including configuring the raw disk description files. Rerun the wizard to create a separate configuration for each guest operating system installed on a raw partition.

Use the following steps to run a guest operating system from a raw disk.

Note: If you use a Windows host's IDE disk in a raw disk configuration, it cannot be
configured as the slave on the secondary IDE channel if the master on that channel is
a CD-ROM drive.

Identify the raw partition on which you plan to install the guest operating system.

Check the guest operating system documentation regarding the type of partition on which the operating system can be installed. For example, operating systems like DOS, Windows 95 and Windows 98 must be installed on the first primary partition while others, like Linux, can be installed on a primary or extended partition on any part of the drive.

Identify an appropriate raw partition or disk for the guest operating system to use. Be sure that the raw partition is not mounted by the Windows host and not in use by others. Also, be sure the raw partition or disk does not have data you will need in the future; if it does, back up that data now.

Choose the physical hard disk to use from the drop-down list. Select whether you want to use the entire disk or use only individual partitions on the disk. Click Next.

If you selected Use individual partitions in the previous step, select which partitions you want to use in the virtual machine. If you selected Use entire disk, this step does not appear.

Click Next.

The partition on which you are installing the guest operating system should be unmapped in the host.

Caution: Corruption is possible if you allow the virtual machine to modify a
partition that is simultaneously mounted under Windows. Since the virtual
machine and guest operating system access a raw disk partition while the host
continues to run Windows, it is critical that you not allow the virtual machine to
modify any partition mounted by the host or in use by another virtual machine.
To safeguard against this problem, be sure the raw disk partition you use for the
virtual machine is not in use by the host.

Windows NT host: Use the Disk Administrator (Start > Programs > Administrative Tools). First highlight the partition that contains the guest operating system, then choose Tools > Assign Drive Letter. In the dialog box, choose Do not assign a drive letter for the partition and click OK. The unmapping happens immediately.

Use the virtual machine settings editor (VM > Settings) if you want to change any configuration options from the wizard defaults  for example, to change the amount of memory allocated to the guest operating system.

At this point you are ready to begin installing the guest operating system onto the raw disk you configured for the virtual machine. For more details, read the installation notes for various guest operating systems in the VMware Guest Operating System Installation Guide, available from the VMware Web site or from the Help menu.

Configuring a Linux Host

Configuring a Linux Host

Identify the raw partition on which the guest operating system will be installed.

Check the guest operating system documentation regarding the type of partition on which the operating system can be installed. For example, operating systems like DOS, Windows 95 and Windows 98 must be installed on the first primary partition while others, like Linux, can be installed on a primary or extended partition on any part of the drive.

Identify an appropriate raw partition or disk for the guest operating system to use. Check that the raw partition is not mounted by the Linux host and not in use by others. Also, be sure the raw partition or disk does not have data you will need in the future; if it does, back up that data now.

Check the operating system partition mounts. Be sure the existing disk partitions that you plan to use in the virtual machine are not mounted by Linux.

Set the device group membership or device ownership.

The master raw disk device or devices need to be readable and writable by the user who runs VMware Workstation. On most distributions, the raw devices, such as /dev/hda (IDE raw disk) and /dev/sdb (SCSI raw disk) belong to group-id disk. If this is the case, you can add VMware Workstation users to the disk group. Another option is to change the owner of the device. Please think carefully about security issues when you explore different options here.

It is a good idea to grant VMware Workstation users access to all /dev/hd[abcd] raw devices that contain operating systems or boot managers, then rely on VMware Workstation's raw disk configuration files to guard access. This provides boot managers access to configuration and other files they may need to boot the operating systems. For example, LILO needs to read /boot on a Linux partition to boot a non-Linux operating system that may be on another drive.

If the raw disk you plan to use has multiple partitions on it already, be aware that certain operating systems (DOS, Windows 95, Windows 98) must be installed on the first primary partition.

Caution: Corruption is possible if you allow the virtual machine to modify a
partition that is simultaneously mounted under the Linux host operating system.
Since the virtual machine and guest operating system access an existing
partition while the host continues to run Linux, it is critical that the virtual
machine not be allowed to modify any partition mounted by the host or in use
by another virtual machine.

To safeguard against this problem, be sure the partition you use for the virtual machine is not mounted under the Linux host.

At this point you are ready to begin installing the guest operating system on the raw disk you configured for the virtual machine. For more details, read the installation notes for various guest operating systems in the VMware Guest Operating System Installation Guide, available from the VMware Web site or from the Help menu.